Micro-liquid enclosure array and its semi-automated assembling system for x-ray free-electron laser diffractive imaging of samples in solution

Abstract

We developed micro-liquid enclosure arrays (MLEAs) for holding solution samples in coherent diffractive imaging (CDI) using X-ray free-electron lasers (XFELs). Hundreds of fully isolated micro-liquid enclosures are arranged in a single MLEA chip for efficient measurement, where each enclosure is destroyed after exposure to a single XFEL pulse. A semi-automated MLEA assembling system was also developed to enclose solution samples into MLEAs efficiently at high precision. We performed XFEL-based CDI experiments using MLEAs and imaged in-solution structures of self-assembled gold nanoparticles. The sample hit rate can be optimized by adjusting solution concentration and we achieved a single-particle hit rate of 31%, which is not far from the theoretical upper limit of 37% derived from the Poisson statistics. MELAs allow us to perform CDI measurement under controlled solution conditions and will help reveal the nanostructures and

<i>Thermus thermophilus</i> polyploid cells directly imaged by X-ray laser diffraction

“…Although the standard focusing size is approximately 1 µm, we detuned it to 1.6 µm (horizontal) × 1.8 µm (vertical), because the PCXSS data analysis requires the incident beam size to be larger than the sample size. The solution containing T. thermophilus cells was enclosed in an MLEA by the semi-automatic alignment system (Kimura et al, 2020), just before PCXSS measurement. MLEAs were placed on precision sample stages in a multiple application X-ray imaging chamber II (MAXIC-II) vacuum chamber (Song et al, 2014), to suppress parasitic scattering from the air.…”

Supplementary document for Three-dimensional structure determination of gold nanotriangles in solution using X-ray free-electron laser single-particle analysis - 5882987.pdf

“…The MLEA has 576 independent liquid enclosures in a 24×24 array [2]. A custom-made flyscan data acquisition system lets us obtain single-shot diffraction patterns from each liquid enclosure of MLEA at up to 30 Hz (i.e., about 20 s per MLEA).…”

Femtosecond X-ray Laser Reveals Intact Sea–Island Structures of Metastable Solid-State Electrolytes for Batteries

“…PCXSS is a coherent diffractive imaging (CDI) 20 enclosure arrays (MLEAs). 21 XFEL facilities have been constructed in many countries over the past decade, 22 and XFELs have been used in various research fields. 23 X-ray lasers have extremely short pulses in the range of femtoseconds, which makes it possible to obtain signals from samples before the onset of radiation damage.…”

“…PCXSS measurements of (Li 2 S) 70 −(P 2 S 5 ) 30 particles were performed at the SPring-8 angstrom compact free-electron laser (SACLA). 26 The particles dispersed in a heptane solvent were enclosed in the MLEA (Figure 2A,B) by a semiautomated assembly system 21 immediately before the PCXSS measurement (see the Supporting Information for details of PCXSS measurements). When the samples are observed in solution, the reconstructed images do not represent the absolute electron density.…”

“…PCXSS is a coherent diffractive imaging (CDI) technique based on X-ray free-electron lasers (XFELs) and microliquid enclosure arrays (MLEAs) . XFEL facilities have been constructed in many countries over the past decade, and XFELs have been used in various research fields .…”